The present invention relates to parametric inversion systems and methods, and more particularly to parametric inversion systems and methods for locating objects.
It is important during excavation to have a precise map of the subsurface so as to avoid damaging existing utilities such as water, gas, and electric lines. For example, when new pipes are to be installed in a certain area, the location of any existing pipes in that area must be known to avoid damage to them when the trenches for the new pipes are being excavated. The lack of accurate subsurface maps for construction sites results in thousands of broken pipes and billions of dollars in repair costs each year.
With conventional pipe-location equipment, a single-frequency current is injected into a pipe, and the magnetic field of this current is measured on the surface with a single hand-held device. If only a single straight pipe is present, the conventional pipe-location equipment can accurately determine the direction and depth of the pipe from the measured values of the magnetic field on the surface. However, if more than one pipe is present or if a pipe bends significantly, this conventional equipment fails to give an accurate estimate of the pipe location. The reason for this failure is that the method used by the conventional pipe-location equipment is based on the assumption that only a single pipe is present in the subsurface. The parametric inversion systems and methods of the present invention are not based on this restrictive assumption, and can be used to accurately locate multiple pipes and bent pipes in complex environments.
A parametric inversion system consistent with the present invention can overcome the disadvantages of conventional systems. Further, a parametric inversion system consistent with the present invention can fit onto a moving vehicle, trailer, or portable housing so that subsurface images can be formed as the system is moving.
The present invention provides a methodology for locating objects using parametric inversion. Additional features and advantages of the invention will be set forth in the description which follows, and in part, will be apparent from the description, or may be learned by practicing the invention. The objectives and other advantages of the invention will be realized and obtained by the method and apparatus particularly pointed out in the written description and the claims hereof as well as in the appended drawings.
To achieve these and other advantages and in accordance with the purpose of the invention, as embodied and broadly described, a system according to the invention locates an object using parametric inversion. An apparatus for locating a target object using parametric inversion comprises a signal injector capable of injecting a signal into the target object, wherein at least a portion of the target object is buried, a magnetic field receiver, a matching processor for matching to a magnetic field received by the magnetic field receiver a parametric magnetic field distribution model corresponding to the target object and at least one other object, and a locating processor for locating the target object using parameters from the parametric magnetic field distribution model.
A method for locating a target object using parametric inversion comprises injecting a signal into the target object, at least a portion of which is buried, receiving a magnetic field radiated from the target object, matching to the received magnetic field a parametric magnetic field distribution model corresponding to the target object and at least one other object, and locating the target object using parameters from the parametric magnetic field distribution model.
Both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.